Calculate the coordinateUncertaintyInMeters
Source:R/dwc_coordinateUncertaintyInMeters.R
dwc_coordinateUncertaintyInMeters.Rd
This function calculates the uncertainty in meters associated with a given set of geographic coordinates. The uncertainty is the sum of two parts:
the uncertainty associated with the coordinate precision given a datum and latitude. This is calculated following the equations found at: http://georeferencing.org/georefcalculator/docs/GeorefGuide.html#imprecision_in_coordinates. If the coordinate reference system is unknown, the default value of 5,359 meters is assigned for this component. See Details.
the uncertainty associated with the GPS recording device. By default this is given as 30 meters.
Usage
dwc_coordinateUncertaintyInMeters(
decimalLatitude,
coordinatePrecision,
geodeticDatum,
gps_uncertainty = 30
)
Arguments
- decimalLatitude
Output of
dwc_coordinates
. Latitude in decimal degrees. See: http://rs.tdwg.org/dwc/terms/decimalLatitude.- coordinatePrecision
Output of
dwc_coordinatePrecision
. The precision of the coordinates in degrees. Value must be between 0.00001 and 1. See: http://rs.tdwg.org/dwc/terms/coordinatePrecision.- geodeticDatum
Output of
dwc_coordinates
. The spatial reference system associated with the coordinates given as an EPSG code as in the example: "EPSG:4326". See: http://rs.tdwg.org/dwc/terms/geodeticDatum.- gps_uncertainty
The uncertainty in meters recorded by the GPS device. Default is 30.
Details
Please see, Wieczorek C, J Wieczorek (2021) Georeferencing Calculator. Available: http://georeferencing.org/georefcalculator/gc.html for more options and further details.
The uncertainty associated with geographic coordinates from an unknown datum
is taken from
https://docs.gbif-uat.org/georeferencing-best-practices/1.0/en/#uncertainty-from-unknown-datum.
Note that this is a worst-case scenario whilst this function lacks the
ability to correctly determine the uncertainty of an unknown datum. If
you have only a small number of locations and an unknown datum, we recommend
using the Wieczorek C, J Wieczorek (2021) Georeferencing Calculator. The
output of the calculator can be copied into R using
dwc_format_gco
.